Forecaster Considerations

revised April 2, 2004; reviewed July 3, 2013

Superstructure ice accretion depends on sea temperature, air temperature,
wind speed, and the freezing point of sea water. For any ice accretion to
take place the air temperature must be below freezing. Once the air
temperature reaches freezing then the sea temperature and wind speed become
important. The lower the sea surface temperature the easier it is for ice
accretion to occur and the faster it will occur. The faster the wind speed
the faster ice will accumulate, particularly if the vessel is moving into the
wind. Ice accretion will take place less readily if the vessel is moving
downwind.